The project consists in the design and calculation of a submarine transport platform. It must be able to carry the submarine while a boat tows the platform to the place where it will have to submerse. At this point, the designed platform will be able to release and isolate the submarine so that it could perform the required missions. From the beginning, the intention was to make a project for a company, it means working in a professional environment in a real project. At the same time, it is a good opportunity to enter in the professional world and apply the knowledge learned during the university. In addition, it is a innovatitive project. The principal objective of the project is to satisfy initial specifications given by the company. These specifications delimit the characteristics of the naval device and denote which missions the platform have to perform. These specifications designate which situations will service and where will this services be done. The main objective of the project is to go round the spiral of projects, making a first design of how the platform could be and should be according to the specifications, and to make the first calcs of the dimension according to the choosing design. Once the specifications are understood, the process is to carry out a market study of all the variants related to the given specifications to define the characteristics of the naval device to be designed along with all delimitations that must have. The initial requirements give an idea of the platform functionalities and the way to use them. The advantages this platform presents to the company are described throughout the document. The most conclusive is to minimize submarine’s time in the water, to be able to make repaires without having to remove it from the water, and to decrease transportation’s cost. The platform will act at the same time as a working platform, where the operators of the submarine could be on it without any problem.